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    Review these resources to learn about the property of "electric charge" and Thomson's model to explain electric charge

    http://www.electricityforum.com/static-electricity.html

    http://www.aip.org/history/electron/jjhome.htm

    Thomson's determination of charge/mass ratio, presented with cartoon graphics. 

     

     

    Cathode ray demonstrations and experiments, showing video of the actual equipment.  Note, a "Crookes Tube" is one type of cathode ray tube.
     
     
     
    Thomson's model can explain the observations we made in-class of interactions between positively and negatively charged materials, as well as neutral (uncharged) materials.  The following resources will help clarify and apply Thomson's model.
     
    Simulation of charged and uncharged interactions, at a particle scale 
     
    Simulation of charge transfer at a particle scale 
     
     
    The following resources are useful to introduce the vocabulary and skills related to objectives 6.3, 6.4 and 6.5
    A student who meets these objectives should also be able to distinguish between the following terms:
    empirical formula vs molecular formula
    ionic compound vs covalent compound vs metal alloy
    formula unit vs molecules
     
    The following videos are recommended for clarifying these concepts and vocabulary:
     
     
     Among the new skills introduced this unit are writing names and forms of ionic or molecular compounds (objective 6.6, 6.7 & 6.8).  chemteam.info provides a wealth of tutorials and practice problem